CN102256236B - System and method for mobility management under separate mapping mechanism - Google Patents

Abstract

The invention relates to a system and a method for mobility management under a separate mapping mechanism. A proxy mobile Internet protocol version 6 (PMIPv6) and the separate mapping mechanism are combined. In an access network of a separate mapping network, the PMIPv6 is greatly improved by the scheme, and three functions comprising an access gateway, a control gateway and a data gateway are designed, thereby realizing the separation of data forwarding and control signaling and the separation of a host identifier and a host position. The separation of the access network and a core network is realized in combination with the separate mapping mechanism.

Description

Mobility management systems under a kind of separate mapping mechanism and method

Technical field

The present invention relates to the mobile management problem of network, particularly relate to mobility management systems and method under a kind of separate mapping mechanism.

Background technology

In early days in the Internet, communication node be fixed more often place mainframe, main frame is without moving, this has also just caused IP address in the time of design conventional internet framework to be endowed dual semanteme, IP address is the identifier of host identities, and it is again the finger URL that represents mainframe network topology location simultaneously.

Mobile IP v 6 (Mobile IPv6, MIPv6) is current commonplace, is also the internet mobility rwan management solution RWAN that comes into question maximum.Its design original intention is not change existing network infrastructure, supports for main frame provides mobile.This feature that does not change network configuration makes MIPv6 need main frame to participate in mobile management, MIPv6 and its derivative network mobility agreement, two stack mobility protocols, many Care-of Address mobility protocol, and every kind of corresponding security mechanism of agreement is to mobile node (Mobile Node, MN) brought very large burden, mobility signaling has taken limited Radio Resource, the safety of MIPv6 acquiescence and cipher key change (IP Security and Internet Key Exchange, IPSec/IKE) mode power consumption and the disposal ability to MN is also a kind of test.

There is in actual applications all drawbacks in Host Based mobility management protocol, researcher wants mobile management to give network side urgently, in August, 2005 internet engineering task group (Internet Engineering Task Force, IETF) the NETLMM(Network-based Localized Mobility Management setting up) working group carried out comprehensive discussion for network mobility management mechanism, and proxy mobile IPv 6 (Proxy Mobile IPv6, PMIPv6) formally proposed in August, 2008.PMIPv6 is a kind of network mobility protocol, and not needing MN to make any change just can provide mobility support for it.

The dual semanteme of internet-ip address is unfavorable for mobile management, and more corresponding agreements are devised the mobile management with Strengthens network for this reason.The identity of main frame and position separation mechanism are the study hotspots in current internet field, can solve preferably the dual Semantic of the IP address of the Internet.2005 the IRTF of internet Task working group (Internet Research Task Force) set up the RRG of route seminar (Routing Research Group) inquire into interconnection path by and address problem.Some famous schools and research institution have carried out a large amount of research and have in succession proposed some tentative programmes on separation mechanism in the world, and more famous scheme has: the eFIT that University of California in Los Angeles proposes, the LANI that Massachusetts Polytechnics proposes, the HLP that University of California Berkeley proposes, HIP, the LISP that Cisco System Co. proposes etc. that Ericsson proposes.

Prior art one related to the present invention

The network model of PMIPv6 agreement as shown in Figure 1.Agreement has been introduced two new functional entitys: Mobile Access Gateway (Mobile Access Gateway, MAG) and local mobile anchor (Local Mobility Anchor, LMA).MAG is at couple in router (Access Router, AR) upper realization, its major function is detect the access of MN and leave, in the time that MAG detects MN mobile, replace MN to carry out mobility management process, carry out the mutual of mobility related signaling with the LMA of MN, set up or delete the communication tunnel between MAG and LMA.Home agent (Home Agent, HA) in effect and the MIPv6 of LMA is similar, and its major function is to safeguard the binding information of MN, guarantees the route accessibility of MN.

PMIPv6 is network mobility management protocol, does not need MN to participate in mobile management, can the complexity of mobile terminal is down to minimum.PMIPv6 allows not install the MN access of mobility protocol, replaces MN to complete the process of mobile management by a MAG in network.Because MN does not need to participate in the Signalling exchange of switching and Binding Update process, thereby reduce the complexity of MN protocol stack, reduced the signaling consumption of air interface, the Radio Resource of preciousness while having saved MN access network.

Itself is also embodying the thought that identity separates with position PMIPv6 agreement, in whole mobility management process, MN utilizes home network prefix (the Home Network Prefix of MAG clean culture, HNP), adopt the home address of the IPv6 form of IPv6 stateless configuration mode generation, in the PMIPv6 territory of MN access, this home address is used to unique mark MN identity.And the MAG of MN access network side act on behalf of the access address of Care-of Address as MN, for identifying the current on-position of MN.In the time that MN is switched to different MAG, its home address is constant, but variation has occurred in the current on-position of MN, and access address is also along with changing, and mobile signaling protocol and user data will carry out addressing to MN by the new access address of MN.

The shortcoming of prior art one

PMIPv6 can only realize limited identity and separate with position in PMIPv6 territory, in the time that MN and the overseas main frame of PMIPv6 communicate, packet from MN is sent to core net at LMA place by decapsulation, in core net, packet is to carry out route with the home address of MN in fact, rather than MN act on behalf of Care-of Address.This makes network attack, and person is easy to utilize the home address of MN to orient the position of MN.

Side by side, the LMA of PMIPv6, in mobility management process, is the control gateway of processing mobile control signal, is again the data gateway that forwards MN data, such design extremely easily causes LMA to become the single fault node in PMIPv6 network configuration, and reliability cannot ensure.Although the NETEXT working group of IETF also has some draft discussion to discuss the security mechanism of LMA, these schemes all can not fundamentally solve control gateway and the double identity characteristic of data gateway of LMA.

Prior art two related to the present invention

In order to solve the mobile management problem under separation mechanism, foreign scholar has proposed some corresponding theory and specific designs, and paper has proposed a kind of PMIPv6 and realized with the scheme of hostid agreement (HIP) combination the mobile management separating on mapping basis.In IETF, also have relevant draft that PMIPv6 and the scheme that separates mapping and combine are discussed, individual draft has proposed a kind of PMIPv6 and has separated the method that (LISP) combine with position with identity and solve the mobile management problem under separation mechanism.

The shortcoming of prior art two

Although these schemes are to separate mapping network, the mobile management problem under PMIPv6 is combined is studied respectively, and paper and draft are all from the angle of expansion PMIPv6, PMIPv6 has been discussed and how has expanded to realize overall ambulant problem.Existing scheme is not all considered the multiplexing problem of LMA data retransmission and control signal management function in PMIPv6 framework.Paper is introduced HIP structure, the more complicated of HIP agreement own, and need main frame that HIP agreement is installed.Draft utilizes LISP to provide overall mobility for PMIPv6, but LISP agreement adopts packaged type to process the packet from user in core net, and does not consider data retransmission and control signal management function separation mechanism.

Summary of the invention

For fear of above the deficiencies in the prior art, the present invention proposes a kind of mobility management systems and the method under separate mapping mechanism.Network mobility protocol PMIPv6 is combined with separate mapping mechanism, make full use of the advantage of separation mechanism and PMIPv6, redesigned a kind of separate mapping network that is more applicable to carrying out mobile management, new network has been realized three kinds of separation mechanisms simultaneously: identity separates with position, data retransmission separates with control signal, Access Network separates with core net.For above three kinds of separation mechanisms, the present invention has introduced IAD (Access GateWay, AGW), has controlled gateway (Control GateWay, CGW) and data gateway (Data GateWay, DGW).It is in Access Network, to realize the mark home address of host identities and routable for identifying the mapping between the access address (be equal to PMIPv6 act on behalf of Care-of Address Proxy-CoA, PCoA) of MN current location that identity separates with position.Data retransmission separates by data gateway and controls gateway with control signal, realize respectively the management to data retransmission and mobile control signal.Access Network separates with core net and uses for reference separation mapping thought, and the home address of MN in Access Network is mapped as in core net overall situation routable core address by address rewrite mechanism.Access Network is realized the access of various types of terminals; Core net solves location management and route technology.

Object of the present invention is achieved through the following technical solutions:

A mobility management systems under separate mapping mechanism, Access Network comprises:

At least one mobile node MN, for connecting access gateway AG W, and is registered to control gateway CGW, obtains mobility service;

At least one access gateway AG W, is arranged at Access Network edge, for monitoring the access of mobile node MN and leaving, and replaces MN and control gateway CGW to carry out the mutual of mobile signaling protocol, sets up tunnel, the data retransmission of responsible MN with data gateway DGW simultaneously;

At least one controls gateway CGW, for realizing the function of local mobile anchor LMA control plane, and carries out Signalling exchange between AGW, and MN is carried out to mobile management;

At least one data gateway DGW, DGW has been used for the data retransmission function of the LMA of PMIPv6 on the one hand, is responsible for setting up communication tunnel with AGW, and DGW completes the couple in router function of separate mapping network simultaneously;

Global map server GMS, mainly completes the map locating function between overall core address and the home address of MN.

A motion management method under separate mapping mechanism, the concrete steps of the method are as follows:

Step 1:MN1 is connected to the AGW1 of Access Network, and AGW1 accesses detection to MN1, and according to the identity descriptor of MN1, MN1 is authenticated;

Step 2:AGW1 sends the positional information of agent binding update PBU with register update MN1 to CGW1, simultaneously for MN1 creates Binding Update list of entries BUL;

Step 3:CGW1 carries out dissection process to agent binding update messages, CGW1 judge the MN1 that registers whether as registering first, Binding Update or separate registration; If registration first, for MN1 sets up the relevant information of a banding cache entry BCE with store M N1, simultaneously by the source address in PBU message, the access address PCoA that the address registration that is also AGW1 is MN1, then CGW1 is that MN1 selects a DGW and send tunnel to set up request message;

Step 4:DGW1 judges MN1 if access first, be used for carrying out map operation with the home address HNP of MN1 from core address of address pool dynamic assignment of local mapping server, if home address and core address are mapping relations one to one, the mapping relations of home address and core address are write in the buffer memory of local mapping server; Meanwhile, DGW1 is sending to global map server GMS about the home address of MN1 and the mapping relations of core address in the buffer memory of local mapping server;

Step 5:DGW1 sets up AGW1 one end to the tunnel of DGW1, and sends tunnel acknowledge message to CGW1;

Step 6:CGW1, after the tunnel of confirming DGW1 end has been set up, sends agent binding to AGW1 and replys PBA packet, has also comprised home network prefix and a mobile option that comprises DGW address of MN1 in PBA;

Step 7:AGW1 is receiving after agent binding reply data bag, obtains available data gateway DGW1 address, sets up the two-way communication tunnel between DGW1; AGW1 obtains the home network prefix of MN1 from PBA message, and with the mode of unicast of advertising of route RA, home network prefix is noticed to MN1, for simulating the home link of MN1; MN1 will allow situation according to the interface of MN1 after receiving advertising of route, uses stateless address configuration mode to configure the home address HoA1 of MN1;

Step 8:MN1 is obtaining after home address HoA1, sends packet to the MNn that is positioned at Access Network 2; Here suppose that MNn has also completed above-mentioned steps 1-7, the home address that MNn obtains at Access Network 2 is HoAn, and first packet is sent to AGW1;

Step 9:AGW1 encapsulates packet, and packet is sent to DGW1 by tunnel style, wherein the AGW1 of the namely current access of MN1 of PCoA1 act on behalf of Care-of Address, DGW1_addr is the address of DGW1 in Access Network side, encapsulation in this encapsulation process and PMIPv6 territory is similar, has completed the mapping between home address HoA and access address PCoA;

Step 10:DGW1 receives after packet, first it is carried out to decapsulation, then DGW1 carries out the inquiry of mapping relations, the core address corresponding to the HNP1 that only has MN1 of the now upper storage of DGW1, first according to the source address HoA1 of packet, local LML1 is carried out to longest prefix match inquiry, obtain qualified HNP1, obtain the mapping relations between HNP1 and core address 1; Because DGW1 is the information of not relevant to HoAn routable core address n now, DGW1 need to carry out alternately with global map server, and by the list of inquiry global map, GML obtains the core address n that HoAn is corresponding;

Step 11:DGW1 is obtaining after the core address map information that all HoA of packet are corresponding, source address to packet, destination address shine upon replacement, and by Packet Generation to DGW2, this address replacement process has completed home address and core address mapping in separate mapping network;

Step 12:DGW2 receives after packet, and does not know the HoA information of core address 1 correspondence, and DGW2 is first to the HoA1 of global map server lookup core address 1 correspondence, and then the source address to packet, destination address carry out demapping replacement;

Step 13:DGW2, due to the two-way communication tunnel of setting up between AGWn, now directly encapsulates packet, and packet is sent to AGWn via tunnel, and DGW2_addr is the address of DGW2 in Access Network side;

Step 14:AGWn carries out decapsulation to packet, and by Packet Generation to MNn;

Step 15:MN1 leaves the AGW1 of Access Network, and AGW1 leaves detection to MN1;

Step 16:AGW1 sends agency to CGW1 and separates Binding Update, and the life span of MN is set to 0, deletes the Binding Update list of entries of MN simultaneously;

Step 17:CGW1 separates binding update messages to agency and carries out dissection process, if separate registration, the relevant information of deleting MN1 in banding cache entry BCE, CGW1 is that MN1 sends tunnel deletion request message afterwards, the content of message comprises the address of MN1 place AGW1, namely the home address of PCoA1 and MN1;

Step 18:DGW1 deletes the relevant entry about MN1 in tunnel cache list TCE, and delete the two-way communication tunnel between AGW1 and DGW1, unless there are other MN also using this tunnel, simultaneously, DGW1 informs the core address of LMS1 to MN1, HNP mapping relations are deleted, and the deletion of these mapping relations are informed to GMS simultaneously;

Step 19:CGW1 sends agency to AGW1 and separates binding response message PBA, and AGW1 deletes the binding entry about MN1 in Binding Update list BUL, and deletes the two-way communication tunnel between AGW1 and DGW1, unless there are other MN also using this tunnel.

The invention has the advantages that:

The present invention combines separate mapping network with network mobility protocol PMIPv6, realized three kinds of separation mechanisms: identity separates with position, data retransmission separates with control signal and Access Network separates with core net.

Access Network adopts identity to separate with position and network mobility management mechanism, and subscriber's main station does not participate in mobile management, has alleviated burden of main machine, is convenient to mobility management scheme and disposes, and is easy to realize the function such as many locals, stream mobility.

Dispose data retransmission and control signal separation mechanism, Access Network can be realized and multiple data gateways can be disposed, control gateway and select different pieces of information gateway according to situations such as Access Network traffic load, eliminate data gateway performance bottleneck problem, reach distributed mobile management object.

Access Network uses different addresses, at Access Network and core net, user is carried out to route from the mapping mechanism of core net, realize completely separating of Access Network and core net, the user behavior that has guaranteed edge network does not affect core network, and the retractility of core network is strengthened.

Accompanying drawing explanation

Fig. 1: PMIPv6 protocol theory figure;

Fig. 2: separation mechanism mobility management systems structure chart;

Fig. 3: separate mapping relations;

Fig. 4: the mutual and data flowchart of mobile signaling protocol.

Embodiment

Separation mechanism network of the present invention is divided into Access Network and core net, and the present invention has adopted a kind of improved PMIPv6 agreement at Access Network, has defined three new functional entity: access gateway AG W, controls gateway CGW and data gateway DGW.Each Access Network is exactly a PMIPv6 territory.LMA in original PMIPv6 is broken down into two parts: CGW and is responsible for processing controls signaling in function, and DGW is responsible for forwarding user data.MAG function in original PMIPv6 changes by AGW and realizes.The present invention adopts separate mapping mechanism between Access Network and core net, and DGW realizes the mapping function that separates between Access Network and core net.To introduce ins and outs of the present invention from three aspects of mobile messaging form that separate mapping relations, functional entity and new definition below.

1, separate mapping relations

The present invention is in order to realize the mobile management under separation mechanism, and in Access Network and core net, packet is separated and shines upon and realize route, need use three class addresses: for the home address of unique identification MN identity, for identifying the access address of current on-position of MN, and for the core address in core net route.Three class address mapping relations logically as shown in Figure 3.

Home address is used for the identity of in the whole network unique identification MN.Access address is for identifying the current on-position of MN, and the data that mail to MN in Access Network will be routed to the position at MN place by access address.Core address only appears at core net, is used for the data of MN to realize the route within the scope of core net.As can be seen from Figure 3, the present invention has mainly adopted twice mapping, is respectively that access address (see following step 9), and home address (is shown in following step 11) to the mapping of core address to the mapping of home address.The unique home network prefix HNP that wherein clearly stipulated in PMIPv6 each MN correspondence in RFC5213; MN, according to corresponding HNP, in conjunction with stateless configuration mode, configures the home address (Home Address, HoA) of a MN; Be that HNP acts on and is equal to HoA in PMIPv6, can represent the uniqueness of MN, so carry out the operations such as the interpolation, inquiry, deletion of the mapping relations between home address and core address with the HNP of MN in this patent.The result of twice mapping is can carry out routing addressing at Access Network and core net respectively from the packet of subscriber's main station.

2, functional entity is divided

IAD (Access Gateway, AGW)

AGW is positioned at Access Network edge, is equivalent to the MAG of PMIPv6 in function, detects the access of MN and leaves, and different is that AGW only carries out the mutual of mobility signaling with CGW, and the concrete form of signaling is with reference to PMIPv6.AGW needs to set up tunnel with DGW simultaneously, is responsible for the data retransmission of MN.

Similar with the MAG of PMIPv6, AGW need to safeguard a Binding Update list (Binding Update List, BUL), concrete data structure as table 1AGW Binding Update list as shown in, the access address that wherein PCoA1 is MN1, represent access be AGW1; PCoA2 is the access address of MN2, and that represent access is AGW2; HNP1 is the local prefix of MN1, the local prefix that HNP2 is MN2; DGW1 is that CGW is the data gateway address that MN1, MN2 distribute.

Table 1

Access address	Home address	Data gateway address
			PCoA1	HNP1	DGW1
PCoA2	HNP2	DGW1

Control gateway (Control Gateway, CGW)

CGW mainly completes the control signal management function of LMA in PMIPv6 in function, is responsible for the Signalling exchange between AGW, and the operation such as foundation, renewal or deletion of the bidirectional tunnel between AGW and DGW is managed in the mobile management of having assisted MN simultaneously.CGW need to safeguard banding cache entry (the Binding Cache Entries of a MN, BCE), concrete data structure is as shown in the banding cache entry of table 2CGW, wherein MN identity descriptor is that AGW is according to 48 bit medium access control address (the Media Access Control of MN, MAC) length converting to can reach the variable length string of 576 bits, as " mn1@example " and " mn2@example ", the form of the format character standardization network access identifier (Network Access Identifier, NAI) of MN identity descriptor.

Table 2

MN identity descriptor	Access address	Home address	Data gateway address
				mn1@example	PCoA1	HNP1	DGW1
mn2@example	PCoA2	HNP2	DGW1

Data gateway (Data Gateway, DGW)

DGW can be divided into two parts in function: on the one hand, DGW completes the data retransmission function of the LMA in PMIPv6, is responsible for setting up communication tunnel with AGW, and the data flow that MN produces is finally all addressed to DGW.Therefore DGW needs to safeguard a tunnel cache entries list (Tunnel Cache Entries, TCE), and concrete data structure is as shown in the tunnel cache entries of table 3DGW:

Table 3

MN identity descriptor	Access address	Home address	Data gateway address
				mn1@example	PCoA1	HNP1	DGW1
mn2@example	PCoA2	HNP2	DGW1

On the other hand, DGW completes the couple in router function of separate mapping network simultaneously, be equivalent to local mapping server (Local Mapping Server, LMS), record the home address of local all MN, mapping relations between core address, from the packet of MN in the time that Access Network mails to core net via DGW, all to inquire about local map listing (the Local Mapping List on LMS, LML), home address is replaced to corresponding core address, the concrete data structure of local map listing is as shown in the local map listing of table 4DGW, wherein core address 1 for LMS1 be MN1 distribute in core net routable core address, core address 2 for LMS1 be MN2 distribute in core net routable core address.

Table 4

Core address	Home address
		Core address
1	HNP1
		Core address
2	HNP2

Global map server (Global Mapping Server, GMS)

Global map server (the Global Mapping Server of separate mapping network, GMS) be deployed in core network, mainly complete the map locating function between overall core address and the home address of MN, when packet mails to core net via DGW, a GMS of packets need inquiry, GMS need to safeguard the global map list that comprises mapping relations between an overall all home address and core address (Global Mapping List, GML), concrete data structure is as shown in the global map list of table 5GMS, wherein core address n be MNn place Access Network LMS be MNn distribute in core net routable core address, HNPn is the home address of MNn.

Table 5

3, mobile messaging formal definition

Mobile management requirements of process of the present invention defines new mobile messaging form, is defined as follows.

The agent binding that in mobile management, CGW sends to AGW is replied and need to be carried DGW address, the address packet of DGW is contained in the mobile option of a new definition, form is as shown in the mobile option of table 6DGW address, and style number is wherein 8 bit unsigned integer, needs IANA to distribute.Reserved field is 24 bit unsigned integer, and this field is initialized as 0 by sender, and recipient must ignore this territory.The DGW address field of 128 bits is for storing the DGW address for data retransmission of being distributed to MN by CGW.

Table 6

The action need such as AGW and tunnel foundation, renewal and the deletion of DGW mutual between CGW and DGW defines new mobile messaging subtype, this patent is with reference to the description to agent binding update form in PMIPv6, defined new tunneled requests message format as shown in table 7 tunneled requests message format, the style number of this mobile messaging needs IANA to distribute.Tunnel signaling sub-type field in this message is 8 bit unsigned integer.This patent has distributed following several value to tunnel signaling subtype: 0 represents tunnel foundation request; 1 represents tunnel update request; 2 represent tunnel removal request.Reserved field is 8 bit unsigned integer, and this field is initialized as 0 by sender, and recipient must ignore this territory.Identification field is 16 bit unsigned integer, for identifying the identity of the sender of this tunneled requests signaling.

Table 7

Similar with the mobile option in mobile IP v 6, this patent has defined the tunneled requests mobile option form in tunneled requests message, as shown in table 8 tunneled requests mobile option form.Sequence-number field is 16 bit unsigned integer, and being used for judgement, whether what comprise be up-to-date tunneled requests signaling.Life span field is 16 bit unsigned integer, represents the life span of this tunneled requests signaling.The home network prefix length of MN is 8 bit unsigned integer, represents the prefix length of the home network of MN.Reserved field is 8 bit unsigned integer.The identity descriptor field of MN is 576 bits, is the unique identification of MN in this PMIPv6 territory.The home network prefix field of MN is 128 bits, and being specially and carrying CGW is the IPv6 home network prefix that MN distributes.The care-of address field of acting on behalf of of MN is 128 bits.The AGW that this field is carried MN agency of trademark registration acts on behalf of the IPv6 address that COA interface index is corresponding, with inform data gateway should and which AGW between carry out the associative operation in tunnel.

Table 8

The present invention has defined new tunnel acknowledge message form as shown in table 9 tunnel acknowledge message form, and the subclass model of this mobile messaging needs IANA to distribute equally.Mode field is 8 bit unsigned integer, specifically can have following value: 0 representative is asked successfully, if this value >=128, the mistake of unknown cause has appearred in expression.Tunnel confirms that sub-type field is 8 bit unsigned integer, specifically can have following value: 0 represents the confirmation that request message is set up in tunnel, 1 confirmation of representative to tunnel update request message, 2 confirmations of representative to tunnel deletion request message.Sequence-number field is 16 bit unsigned integer, and whether what be used for that judgement comprises is that signaling is confirmed in up-to-date tunnel.Life span field is 16 bit unsigned integer, represents the life span of this tunnel confirmation signaling.MN identify label field is 576 bits, is the unique identification of MN.

Table 9

In conjunction with the mobility management systems Fig. 2 under separate mapping mechanism, send packet as example take the MN1 that is positioned at Access Network 1 to the MNn that is positioned at Access Network 2, from MN enters Access Network 1, to leaving Access Network 1, the basic procedure of the mutual and datum plane of mobile signaling protocol described in the invention as shown in Figure 4.

The home address of mobile node does not use in core net as overall routing address, can only use in the Access Network of access address PCoA under it and carry out route.In the time that the mobile node MN 1 in Access Network 1 is used HoA1 to mobile node MN n initiating communication in Access Network 2, as shown in Figure 4, detailed step is as follows for signalling interactive process and data transmission procedure:

Step 1:MN1 is connected to the AGW1 of Access Network, and AGW1 accesses detection to MN1, and according to the identity descriptor of MN1, MN1 is authenticated;

Step 2:AGW1 sends the positional information of agent binding update (Proxy Binding Update, PBU) with register update MN1 to CGW1, simultaneously for MN1 creates Binding Update list of entries BUL, as shown in table 1;

Step 3:CGW1 carries out dissection process to agent binding update messages, the MN1 of CGW1 judgement registration be register first, Binding Update or separate registration.If registration first, for MN1 sets up the relevant information of a banding cache entry BCE with store M N1, is registered as the source address in PBU message (being the address of AGW1) the access address PCoA of MN simultaneously.CGW1 is that MN1 selects a DGW afterwards, here take DGW1 as example, and sends tunnel and sets up request message, and concrete form is shown in aforesaid mobile messaging formal definition;

Step 4:DGW1 judges MN1 if access for the first time, be used for carrying out map operation with the home address HNP of MN1 from core address of address pool dynamic assignment of local mapping server, the present invention supposes that home address and core address are mapping relations one to one, and the mapping relations of home address and core address are write in the buffer memory of local mapping server.Meanwhile, DGW1 is sending to global map server GMS about the home address of MN1 and the mapping relations of core address in the buffer memory of local mapping server;

Step 5:DGW1 sets up AGW1 one end to the tunnel of DGW1, and sends tunnel acknowledge message to CGW1;

Step 6:CGW1 is after the tunnel of confirming DGW1 end has been set up, send agent binding to AGW1 and reply (Proxy Binding Acknowledgement, PBA) packet, in PBA, also comprised home network prefix and a mobile option that comprises DGW address of MN1, concrete form is shown in aforesaid mobile messaging formal definition;

Step 7:AGW1 is receiving after agent binding reply data bag, obtains available data gateway DGW address, sets up the two-way communication tunnel between DGW1.AGW1 obtains the home network prefix of MN1 from PBA message, and with the mode of unicast of advertising of route (Route Advertisement, RA), home network prefix is noticed to MN1, for simulating the home link of MN1.MN1 will allow situation according to the interface of MN1 after receiving advertising of route, uses stateless address configuration mode to configure the home address HoA1 of MN1;

Step 8:MN1 is obtaining after home address HoA1, can send packet to the MNn that is positioned at Access Network 2.Here suppose also completing steps 1-7 of MNn, the home address that MNn obtains at Access Network 2 is HoAn.First packet is sent to AGW1, and data packet format is as shown in table 10MN1 to AGW1 data packet format;

Table 10

Destination address	Source address	Content
			HoAn	HoA1	Data

Step 9:AGW1 encapsulates as shown in table 11AGW1 to DGW1 data packet format packet, and packet is sent to DGW1 by tunnel style, wherein the AGW1 of the namely current access of MN1 of PCoA1 act on behalf of Care-of Address, DGW1_addr is the address of DGW1 in Access Network side, encapsulation in this encapsulation process and PMIPv6 territory is similar, has completed the mapping between home address HoA and access address PCoA;

Table 11

Destination address	Source address	Destination address	Source address	Content
					DGW1_addr	PCoA1	HoAn	HoA1	Data

Step 10:DGW1 receives after packet, first it is carried out to decapsulation as shown in the packet format after table 12DGW1 decapsulation.Then DGW1 carries out the inquiry of mapping relations, the core address corresponding to the HNP1 that only has MN1 of the now upper storage of DGW1, first the source address HoA1 of packet is carried out to longest prefix match inquiry to local LML1, obtain qualified HNP1, obtain the mapping relations between HNP1 and core address 1; Because DGW1 is the information of not relevant to HoAn routable core address n now, DGW1 need to carry out alternately with global map server, and by the list of inquiry global map, GML obtains the core address n that HoAn is corresponding;

Table 12

Destination address	Source address	Content
			HoAn	HoA1	Data

Step 11:DGW1 is obtaining after the core address map information that all HoA of packet are corresponding, source address to packet, destination address shine upon to be replaced as shown in the data packet format after table 13DGW1 mapping, and by Packet Generation to DGW2, this address replacement process has completed home address and core address mapping in separate mapping network;

Table 13

Destination address	Source address	Content
			Core address n	Core address	1	Data

Step 12:DGW2 receives after packet, and do not know the HoA information of core address 1 correspondence, DGW2 is first to the HoA1 of global map server lookup core address 1 correspondence, and then the source address to packet, destination address carry out demapping replacement as shown in the data packet format after table 14DGW2 demapping;

Table 14

Destination address	Source address	Content
			HoAn	HoA1	Data

Step 13:DGW2 is due to the two-way communication tunnel of setting up between AGWn, now directly packet is encapsulated as shown in the data packet format of table 15DGW2 to AGWn, and packet is sent to AGWn via tunnel, DGW2_addr is the address of DGW2 in Access Network side;

Table 15

Destination address	Source address	Destination address	Source address	Content
					PCoAn	DGW2_addr	HoAn	HoA1	Data

Step 14:AGWn to packet carry out decapsulation as table 16AGWn to MNn data packet format as shown in, and by Packet Generation to MNn;

Table 16

Destination address	Source address	Content
			HoAn	HoA1	Data

Step 15:MN1 leaves the AGW1 of Access Network, and AGW1 leaves detection to MN1;

Step 16:AGW1 sends agency to CGW1 and separates Binding Update, and the life span of MN is set to 0, deletes the Binding Update list of entries of MN simultaneously;

Step 17:CGW1 separates binding update messages to agency and carries out dissection process.If separate registration, the relevant information of deleting MN1 in banding cache entry BCE, CGW1 is that MN1 sends tunnel deletion request message afterwards, concrete form is shown in aforesaid mobile messaging formal definition, and the content of message comprises the address (namely PCoA1) of MN1 place AGW1 and the home address of MN1;

Step 18:DGW1 deletes the relevant entry about MN1 in tunnel cache list TCE, and delete the two-way communication tunnel between AGW1 and DGW1, unless there are other MN also using this tunnel, simultaneously, DGW1 informs the < core address of LMS1 to MN1, HNP> mapping relations are deleted, and the deletion of these mapping relations are informed to GMS simultaneously;

Step 19:CGW1 sends agency to AGW1 and separates binding response message PBA, and AGW1 deletes the binding entry about MN1 in Binding Update list BUL, and deletes the two-way communication tunnel between AGW1 and DGW1, unless there are other MN also using this tunnel.

Separation mechanism mobility support system as herein described, take AGW, CGW, DGW as major function entity, by a series of interacting messages between them, completes the effective management to positions of mobile nodes, guarantees the correct foundation of communication connection.

Claims (2)

1. the mobility management systems under separate mapping mechanism, is characterized in that, the Access Network of described system comprises:

At least one mobile node MN, for connecting access gateway AG W, and is registered to control gateway CGW, obtains mobility service;

At least one access gateway AG W, is arranged at Access Network edge, for monitoring the access of mobile node MN and leaving, and replaces MN and control gateway CGW to carry out the mutual of mobile signaling protocol, sets up tunnel, the data retransmission of responsible MN with data gateway DGW simultaneously;

At least one controls gateway CGW, for realizing the function of local mobile anchor LMA control plane, and carries out Signalling exchange between AGW, and MN is carried out to mobile management;

At least one data gateway DGW, DGW has been used for the data retransmission function of the LMA of PMIPv6 on the one hand, is responsible for setting up communication tunnel with AGW, and DGW completes the couple in router function of separate mapping network simultaneously;

Described system also comprises: be positioned at the global map server GMS of core net, mainly complete the map locating function between overall core address and the home address of MN.

2. the motion management method under separate mapping mechanism, is characterized in that: the concrete steps of the method are as follows:

Step 1: mobile node MN 1 is connected to the access gateway AG W1 of Access Network, AGW1 accesses detection to MN1, and according to the identity descriptor of MN1, MN1 is authenticated;

Step 2:AGW1 sends the positional information of agent binding update PBU with register update MN1 to controlling gateway CGW1, simultaneously for MN1 creates Binding Update list of entries BUL;

Step 3:CGW1 carries out dissection process to agent binding update messages, CGW1 judge the MN1 that registers whether as registering first, Binding Update or separate registration; If registration first, for MN1 sets up the relevant information of a banding cache entry BCE with store M N1, simultaneously by the source address in PBU message, also the access address PCoA that the address registration that is AGW1 is MN1, then CGW1 is that MN1 selects a data gateway DGW and send tunnel to set up request message;

Step 4:DGW1 judges MN1 if access first, be used for carrying out map operation with the home address HoA of MN1 from core address of address pool dynamic assignment of local mapping server, if home address and core address are mapping relations one to one, the mapping relations of home address and core address are write in the buffer memory of local mapping server; Meanwhile, DGW1 is sending to global map server GMS about the home address of MN1 and the mapping relations of core address in the buffer memory of local mapping server;

Step 5:DGW1 sets up AGW1 one end to the tunnel of DGW1, and sends tunnel acknowledge message to CGW1;

Step 6:CGW1, after the tunnel of confirming DGW1 end has been set up, sends agent binding to AGW1 and replys PBA packet, has also comprised home network prefix and a mobile option that comprises DGW address of MN1 in PBA;

Step 7:AGW1 is receiving after agent binding reply data bag, obtains available data gateway DGW1 address, sets up the two-way communication tunnel between DGW1; AGW1 obtains the home network prefix of MN1 from PBA message, and with the mode of unicast of advertising of route RA, home network prefix is noticed to MN1, for simulating the home link of MN1; MN1 will allow situation according to the interface of MN1 after receiving advertising of route, uses stateless address configuration mode to configure the home address HoA1 of MN1;

Step 8:MN1 is obtaining after home address HoA1, sends packet to the MNn that is positioned at Access Network 2; MNn described here has also completed above-mentioned steps 1-7, and the home address that MNn obtains at Access Network 2 is HoAn, and first packet is sent to AGW1;

Step 9:AGW1 encapsulates packet, and packet is sent to DGW1 by tunnel style, wherein the AGW1 of the namely current access of MN1 of PCoA1 act on behalf of Care-of Address, DGW1_addr is the address of DGW1 in Access Network side, encapsulation in this encapsulation process and PMIPv6 territory is similar, has completed the mapping between home address HoA and access address PCoA;

Step 10:DGW1 receives after packet, first it is carried out to decapsulation, then DGW1 carries out the inquiry of mapping relations, the core address corresponding to the HoA1 that only has MN1 of the now upper storage of DGW1, first according to the source address HoA1 of packet, local map listing LML1 is carried out to longest prefix match inquiry, obtain qualified HoA1, obtain the mapping relations between HoA1 and core address 1; Because DGW1 is the information of not relevant to HoAn routable core address n now, DGW1 need to carry out alternately with global map server, and by the list of inquiry global map, GML obtains the core address n that HoAn is corresponding;

Step 11:DGW1 is obtaining after the core address map information that all HoA of packet are corresponding, source address to packet, destination address shine upon replacement, and by Packet Generation to DGW2, this address replacement process has completed home address and core address mapping in separate mapping network;

Step 12:DGW2 receives after packet, and does not know the HoA information of core address 1 correspondence, and DGW2 is first to the HoA1 of global map server lookup core address 1 correspondence, and then the source address to packet, destination address carry out demapping replacement;

Step 13:DGW2, due to the two-way communication tunnel of setting up between AGWn, now directly encapsulates packet, and packet is sent to AGWn via tunnel, and DGW2_addr is the address of DGW2 in Access Network side;

Step 14:AGWn carries out decapsulation to packet, and by Packet Generation to MNn;

Step 15:MN1 leaves the AGW1 of Access Network, and AGW1 leaves detection to MN1;

Step 16:AGW1 sends agency to CGW1 and separates Binding Update, and the life span of MN is set to 0, deletes the Binding Update list of entries of MN simultaneously;

Step 17:CGW1 separates binding update messages to agency and carries out dissection process, if separate registration, the relevant information of deleting MN1 in banding cache entry BCE, CGW1 is that MN1 sends tunnel deletion request message afterwards, the content of message comprises the address of MN1 place AGW1, namely the home address of PCoA1 and MN1;

Step 18:DGW1 deletes the relevant entry about MN1 in tunnel cache list TCE, and delete the two-way communication tunnel between AGW1 and DGW1, unless there are other MN also using this tunnel, simultaneously, DGW1 informs the core address of local mapping server LMS1 to MN1, HoA mapping relations are deleted, and the deletion of these mapping relations are informed to GMS simultaneously;

Step 19:CGW1 sends agency to AGW1 and separates binding response message PBA, and AGW1 deletes the binding entry about MN1 in Binding Update list BUL, and deletes the two-way communication tunnel between AGW1 and DGW1, unless there are other MN also using this tunnel.

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